1. Field of the Invention
The present invention relates to a scanning display device for forming an image by two-dimensional scanning with a light beam, and more particularly to a scanning display device having a plurality of scanning surfaces. In addition, the present invention relates to a video image taking apparatus such as a digital still camera or a digital video camcorder, having the scanning display device serving as an electronic viewfinder.
2. Related Background Art
An apparatus for recording an image obtained by an image pickup device represented by a charge-coupled device (CCD) includes a so-called digital stall camera (hereinafter referred to as a DSC) and a digital video camcorder (hereinafter referred to as a DVC). The DSC and the DVC each are generally provided with a finder for exhibiting an image taking area to a user.
For a large number of apparatuses, an optical view finder having a specific optical system is used as the finder in addition to an optical system for performing image pickup by a CCD or the like. However, in the case of such an optical view finder system using the optical system in addition to the optical system utilized for image pickup, there is a problem in that an image taking region observed through the finder is different from an image taking region of an image which is actually taken by a so-called parallax, in particular, in close-up image taking.
In contrast to this, there is an electronic viewfinder for displaying, as an image, a signal from the image pickup device such as the CCD on a display panel like a small size liquid crystal panel and enlarging the image for observation using an optical system. According to the electronic viewfinder, without being processed, the signal from the image pickup device is utilized. Therefore, an image having same view angle as that of the image, which is actually to be taken, can be observed, so that the image taking region can be determined with parallax error-free view.
An electronic viewfinder system using a scanning image display device as described in Japanese Patent Application Laid-Open No. H11-084291 has been proposed as an electronic viewfinder system in which a high-resolution image can be obtained. The scanning image display device is of a finder system which does not utilize a conventional display device such as a liquid crystal panel, and can obtain the high-resolution image. Because the liquid crystal panel or the like is not utilized as the display device, for example, a manufacturing problem such as the occurrence of a pixel defect is unlikely to cause.
On the other hand, for a large number of DSCs and DVCs, a direct-view display element having a size of several inches is provided on the side surface or rear surface of a main body in addition to a conventional near eye viewfinder. The direct-view display element is utilized instead of the viewfinder by displaying the signal from the image pickup device without being processed as in the electronic viewfinder. In this case, as compared with the conventional viewfinder, an effect such as an improvement of the degree of freedom of posture in image taking is obtained. The direct-view display element is also used to display an image taking condition, a battery level, the number of taken images, and the like. Therefore, an effect such as an improvement of convenience is large when the DSC or the DVC is used.
However, the direct-view display element has a defect that display is hard to be viewed in an environment of lighted surroundings such as the outdoors on a bright day. Therefore, the direct-view display element cannot always serve as the viewfinder.
Therefore, in the DSC and the DVC, in order that an image taking region is checked regardless of a state such as lighting of the surroundings and convenience that information including a current image taking condition is also displayed is ensured, it is preferable that the direct-view display element is provided on the side surface or rear surface in addition to the electronic view finder.
When the DSC or the DVC is provided with two display systems, that is, both the electronic viewfinder and the direct-view display element, it is necessary to provide at least two display devices such as liquid crystal panels. Therefore, a reduction in size and weight of an image taking apparatus becomes difficult, so that an increase in cost of the image taking apparatus occurs.